1. Technical Field
The present invention relates to a retainer of a roller bearing, such as a radial ball bearing and a radial roller bearing, and particularly to a retainer of a sealed bearing with grease filled therein or a retainer for balls or rollers of a sealed bearing.
2. Background Art
A radial ball bearing has a retainer for retaining therein plural balls that are arranged in a freely rotatable manner in a circumferential direction between an outer ring and an inner ring.
A sealed bearing with grease filled therein has seal rings, such as those made of iron plate, arranged on both the lateral end surfaces between the outer ring and the inner ring to prevent leakage of grease filled inside of the bearing. There is an example of such a roller bearing, in which an inside space of a retainer of a ball bearing is increased to increase the durability of the ball bearing (e.g., Patent Document 1: Japanese Patent Application Laid-open No. 2005-214257).